JPH09105393A - Gas compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To aim at the realization of a gas compressor small in such a pulsation as being leaked to the outside and yet higher in stillness. SOLUTION: A rear side housing side plate 3 is composed of reducing a passage sectional area, insomuch that internal pressure in a compression space is not extremely raised up in a range from a first discharge port 18 to a second discharge port of an oil separator 11, and of installing a silencing passage 21 having secured a passage distance longer, insofar as possible. In succession, a top surface of this silencing passage 21 is hermetically sealed and locked by the oil separator 11. In addition, a sectional area of the second discharge port 20 of the oil separator 11 is constituted to make it smaller, insomuch that pressure in the compression space is not abnormally raised up.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas compressor used as a refrigerant compressor or the like of a vehicle air conditioner, and more particularly to a gas compressor for gradually reducing discharge pulsation of a gas compressor to reduce noise.

[0002]

2. Description of the Related Art Conventionally, in a gas compressor, suction of refrigerant gas,
Since the refrigerant gas is sent under pressure in each step of compression and discharge, a specific pressure fluctuation (hereinafter referred to as pulsation) is generated in the discharge chamber and transmitted from the discharge port to the outside of the compressor. In addition, this caused noise corresponding to the pulsation. The situation during this period will be described by taking a conventional gas compressor as an example. FIG. 5 shows a vertical sectional view of a conventional gas compressor, and FIG. 6 shows a sectional view taken along the line AA. The gas compressor mainly comprises a housing 1 having a substantially elliptical inner peripheral surface, and a cylinder 4 closed by a front housing side plate 2 and a rear housing side plate 3 for fixing front and rear end surfaces of the housing 1, respectively. . A rotor 6 is rotatably supported by a shaft 5 in the cylinder 4.
And a vane 7 that is inserted into and retracted from the rotor 6 in a radial direction. Between the cylinder 4 and the rotor 6 whose front and rear end faces are closed, two compression chambers 8 are defined at substantially symmetric positions.

The housing 1 fixed to the front housing side plate 2 and the rear housing side plate 3 is fitted in a rear housing 9. A front housing 10 is fixed to the outer end surface of the front housing side plate 2. An oil separator 11 for separating oil from the refrigerant gas is fixed to the outer end surface of the rear housing side plate 3. A refrigerant gas discharge port 12 is formed on the upper surface of the rear housing 9, and a refrigerant gas suction port 13 is formed on the upper surface of the front housing 10. The discharge port 12 communicates with a discharge chamber 14 defined by the rear housing side plate 3 and the rear housing 9, and the suction port 13 communicates with a suction chamber 15 defined by the front housing side plate 2 and the front housing 10. ing. A cylinder discharge port 16 for discharging a compressed refrigerant gas and a reed valve 17 whose one end is openably and closably fastened at the other end are attached to the housing 1 in the circumferential direction of the housing 1. Are provided at substantially symmetrical positions.

In this structure, the refrigerant gas compressed in each compression chamber 8 is discharged from the cylinder discharge port 16 to the reed valve 1.
The first discharge port 18 (not shown) that penetrates the rear housing side plate 3 is passed through. After that, the refrigerant gas is discharged into the discharge chamber 14 from the wire mesh-shaped oil separator 19 fitted in the oil separator 11. At that time, the refrigerant gas separated from the oil component contained in the refrigerant gas and having the oil component removed is guided from the discharge port 12 to a hose (not shown) and sent to a condenser or the like. Five vanes 7 are inserted into the rotor 6 shown in FIG. 6 and are involved in each process of suction, compression and discharge of the refrigerant gas. Since the cylinder discharge ports 16 are provided at substantially opposite positions of the housing 1, as the rotor 6 rotates, the gas pressure fluctuations from one cylinder discharge port 5 to each rotation of the rotor 6 occur five times. Further, since the odd number of vanes is used, the gas pressure fluctuations having a phase difference of 180 degrees are generated from the other cylinder discharge ports 16 facing each other. Therefore,
From the discharge port 12, the synthesized gas pressure fluctuation, that is, pulsation corresponding to 10 times per one rotation of the rotor 6 is generated.

The number of pulsations per second has a wide range of variation because the shaft 5 of the gas compressor is rotatably driven in conjunction with an on-vehicle engine or the like. For example, the engine rotation has a fluctuation range of about 1000 RPM at idling and about 7,000 to 8000 RPM in the red zone. That is, pulsation is generated according to the number of rotations, and at the same time, it causes noise with large frequency fluctuations. In order to reduce such pulsation, a muffler is conventionally used as a discharge port 12 of a gas compressor.
It was known to be attached to the end of
No. 6005).

[0006]

However, in the above-described conventional sound deadening technique, the gas compressor is upsized and the manufacturing cost is increased by the amount corresponding to the muffler. Furthermore, the discharge chamber 14
There is a risk that noise leaking from the rear housing 9 to the outside cannot be eliminated. The present invention has been made in view of such conventional problems, with the quieter vehicle side in recent years, the pulsation leaked to the outside is small and more quiet, the gas compression is small and lightweight, and the manufacturing cost is low. The purpose is to provide a machine.

[0007]

For this reason, the present invention (Claim 1) provides one or a plurality of first side plates for allowing the front housing side plates and the refrigerant gas to pass through the both end surfaces of the housing.
A cylinder closed by a rear housing side plate having a discharge port, a rotor supported by a shaft in the cylinder to rotate, and one or a plurality of sections defined by an outer peripheral surface of the rotor and an inner peripheral surface of the cylinder. And a second discharge port fixed to the outer end surface of the rear housing side plate for discharging the refrigerant gas pressurized in the compression chamber and separating the oil component in the refrigerant gas. In a gas compressor provided with an oil separator, a discharge chamber defined by the rear housing side plate and a rear housing fixed to a peripheral end surface of the rear housing side plate, an outer end surface of the rear housing side plate or The one or more first outlets of the rear housing side plate to the one or more second outlets of the oil separator are formed on the inner end surface of the oil separator. Plural to the extent that the internal pressure does not excessively increase the compression chamber reduced cross-sectional area, and was constructed by disposing the silencing passage ensured a passage distance long.

Further, according to the present invention (claim 2), both end surfaces of the housing are closed by the front housing side plate and the rear housing side plate having one or a plurality of first discharge ports for passing the refrigerant gas. A cylinder, a rotor supported by a shaft to rotate in the cylinder, one or a plurality of compression chambers defined by the outer peripheral surface of the rotor and the inner peripheral surface of the cylinder, and the outer side of the rear housing side plate. An oil separator fixed to an end face, having one or a plurality of second discharge ports for discharging a refrigerant gas pressurized in the compression chamber and separating an oil component in the refrigerant gas; the rear housing side plate; A gas compressor having a discharge chamber defined by a rear housing fixed to a peripheral end surface of a rear housing side plate, wherein one or a plurality of second discharge ports of the oil separator are provided. Sectional area was constructed small enough to not excessively raise the internal pressure of the one or more compression chambers.

Further, according to the present invention (claim 3), the silencing passage is divided into a plurality of passages, and the total passage of the silencing passages is cut to such an extent that the internal pressure of the one or more compression chambers is not extremely increased. The area was reduced.

Further, according to the present invention (claim 4), at least one cavity having a cross-sectional area larger than the cross-sectional area of the muffler passage is arranged in the middle of the muffler passage.

Further, in the present invention (claim 5), the cross-sectional area of one or a plurality of second discharge ports of the oil separator is made small so that the internal pressure of the one or a plurality of compression chambers is not extremely increased. Configured.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. Referring to FIG. 1 showing a first embodiment of the present invention, a compression mechanism has front and rear end surfaces of a housing 1 at a front housing side plate 2 and a rear housing side plate 3.
It corresponds to the cylinder 4 in which the rotor 6 having the vane 7 fitted therein is closed (hereinafter, the same). An oil separator 11 for separating oil is fixed to the outer end surface of the rear housing side plate 3. In place of the wire-mesh-shaped oil separator 19 fitted in the oil separator 11, the discharge port 20 of the oil separator 11 has a small pipe cross-sectional area so that the pressure in the compression chamber 8 does not rise abnormally, and For example, one end of a copper pipe 25 having a long path length is joined. The other end of the copper pipe 25 is opened inside the discharge chamber 14. Next, the operation will be described. When sound propagates in a thin tube, the sound attenuation varies depending on the material of the tube wall, but even with a smooth metal tube, the amount of attenuation is greater than that in air. Ki
According to rchhof, the damping constant α is

(Equation 1) However, C: speed of sound [m] R: radius of tube In case of square tube, the above formula is

(Equation 2) However, C: sound velocity [m] D: inner diameter. That is, the sound attenuation by the pipe is inversely proportional to the radius and inner diameter of the pipe and proportional to the length of the pipe. According to the result of many experiments, the attenuation is 10 to 15 due to other factors than the value calculated by Equation 1.
Grows by a percentage.

In the present embodiment, the copper pipe 25 is used for the above reason.
Was adopted on a trial basis, the cross-sectional area of the pipeline was made small enough not to raise the pressure in the compression chamber 8 abnormally, and the pipeline length was secured as long as possible. Here, the conduit cross-sectional area that does not abnormally increase the pressure in the compression chamber 8 is one assumption that the inventor considered the open area when the reed valve 17 was opened to the maximum (hereinafter, the same). As a result, the pulsation in the discharge port 12 became extremely small. It was also confirmed that the longer the pipe length, the greater the noise attenuation. Next, FIG. 2 shows a second embodiment of the present invention. In FIG.
(A) is a simplified configuration diagram of the gas compressor, and (B) is an external view of the rear housing side plate 3.

The rear housing side plate 3 has a first discharge port 18
To the second discharge port 20 of the oil separator 11, the sound deadening passage 2 having a small passage cross-sectional area and a passage distance as long as possible so that the internal pressure of the compression chamber 8 is not extremely increased.
1 is provided. And the muffling passage 21
The upper surface of is sealed and fixed by an oil separator 11. Moreover, the cross-sectional area S1 of the second discharge port 20 of the oil separator 11 is configured to be small enough not to raise the pressure in the compression chamber 8 abnormally. Next, the operation will be described. As described in Formula 1 or Formula 2, in order to attenuate noise, it is necessary to secure a small passage cross-sectional area and a long passage distance. However, since various existing bolt holes are present in the rear housing side plate 3, the sound deadening passages 21 are arranged so as to meander in a manner avoiding bolt holes (not shown) as shown in FIG. 2B. I set it up. In this embodiment, the passage distance of the muffling passage 21 is set to about 15 cm. as a result,
I was able to reduce the noise to a considerable extent.

Although a closing lid may be specially provided on the upper surface of the muffling passage 21, the number of parts can be reduced by also using the oil separator 11. Further, although the muffling passage 21 is arranged on the outer end surface of the rear housing side plate 3, it may be arranged on the inner end surface of the oil separator 11. According to the present embodiment, the number of parts is reduced as compared with the first embodiment because the copper pipe 25 is not used, the assembly process is the same as the conventional one, the manufacturing cost is hardly increased, and the reliability and durability are the same as the conventional one. There are advantages such as. On the other hand, when sound propagates in a tube, if there is a change in cross section or impedance change such as pores communicating to the outside, part of the sound is reflected and as a result propagation of a specific frequency can be reduced. I can. The amount of noise attenuation in this case is related to the cross-sectional area change ratio of the pipe. According to the calculation based on the acoustic impedance, the attenuation is about 0.5 dB when the cross-sectional area change ratio S2 / S1 of the tube is 2 times, about 2 dB when the ratio is 3 times, and about 5 dB when the ratio is 10 times. . Therefore, by changing the cross-sectional area S1 of the second discharge port 20 of the oil separator 11 to such an extent that the pressure in the compression chamber 8 does not rise abnormally, and discharging into the discharge chambers 14 having different cross-sectional areas S2, the cross-sectional change The sound attenuation effect by S2 / S1 can be obtained. On the other hand, although the cross-sectional area of the discharge port 12 is the same as the conventional one, it is still sufficiently smaller than the cross-sectional area S2. In the change S2 / S1 of the cross-sectional area in this case, since the volume of the discharge chamber 14 is large and a large ratio can be secured, the sound damping effect is large.

In this way, by disposing the sound deadening passage 21 in the rear housing side plate 3 and reducing the cross-sectional area S1 of the second discharge port 20 of the oil separator 11, there is no major design change in the gas compressor. It was possible to obtain a damping effect of about 1/10 in pressure value at the outlet of the discharge port 12. This corresponds to an attenuation of 20 dB. Next, FIG. 3 shows a third embodiment of the present invention. In FIG. 3, the rear housing side plate 3 and the oil separator 11 have the same configurations as those of the second embodiment described above, but the rear housing side plate 3
An auxiliary side plate 22 having a sound deadening passage 21 is further interposed between the oil separator 11 and the oil separator 11. Next, the operation will be described. As compared with the second embodiment, the passage distance can be made longer by the extension of the muffling passage 21 by the auxiliary side plate 22, and the noise can be further reduced. By stacking the auxiliary side plates 22 in a plurality of stages, the passage distance of the muffling passage 21 can be further lengthened. However, since there are disadvantages such as an increase in the number of parts of the auxiliary side plate 22 and a decrease in the volume of the discharge chamber 14, it is necessary to consider in a balanced manner.

Next, FIG. 4 shows a fourth embodiment of the present invention. In the above-described second embodiment, the case where one compression chamber 8 is provided and the rear housing side plate 3 has one first discharge port 18 is illustrated, but in FIG. 4, two compression chambers 8A and 8B are provided. And the rear housing side plate 3 has two first discharge ports 18A and 18B corresponding to the respective compression chambers. In FIG. 4A, the refrigerant gas discharged from the two first discharge ports 18A and 18B is discharged to the two second discharge ports 20A and 20B via the two muffling passages 21A and 21B, respectively. Indicate the case. In this case, the pulsating components having the half-wavelength phase difference generated in the two compression chambers 8A and 8B join together in the discharge chamber 14. The muffling passages 21A and 21B are provided in the compression chamber 8
It is the same as in the second embodiment that it is preferable that the passage cross-sectional area is small and the pipe length is as long as possible so that the internal pressures in A and 8B are not extremely increased. The same applies to the fact that the area is small and the pipeline length is long).

In FIG. 4B, the second first discharge port 18A,
Refrigerant gas exhaled from 18B,
A case is shown in which, after merging once in the plane of the rear housing side plate 3 via A and 21B, and then further discharged to one discharge port 20 via the sound deadening passage 21C. In this case, the pulsating components having the half-wavelength phase difference generated in the two compression chambers 8A and 8B merge in the plane of the rear housing side plate 3 and the pulsating peaks and troughs interfere with each other. It will be. That is, a canceling effect due to the phase difference can be expected. At this time, it has been confirmed from the inventor's experimental results that the effect of canceling the phase difference is greater if the pipe lengths of the muffling passages 21A and 21B before the merging are equal to each other (the pipe length before the merging is longer). The same applies to points that are equidistant). In FIG. 4C, the second first discharge port 1
The case where the refrigerant gas discharged from 8A and 18B joins immediately before being discharged to the one discharge port 20 via the muffling passages 21A and 21B is shown. In this case, the second compression chamber 8
The pulsating components having a half-wavelength phase difference generated in A and 8B merge immediately before being discharged to the discharge port 20 of the rear housing side plate 3, and the phases cancel each other.

In FIG. 4D, the second first discharge port 18A,
The case where the refrigerant gas discharged from 18B merges immediately before being discharged to one discharge port 20 via the muffling passages 21a and 21b each composed of a plurality of lines is shown. That is, FIG.
The silencing passages 21A and 21B of (C) are replaced by a plurality of silencing passages 2
This corresponds to the case of being divided into 1a and 21b. Such division of the sound deadening passage can also be applied to FIG. By dividing the muffling passage, it is possible to further reduce the passage cross-sectional area for each one, and it is possible to further expect the effect of attenuation by the formula 1 or the formula 2. Further, it is possible to sufficiently secure the total of the passage cross-sectional areas of the divided muffling passages, and it is not necessary to consider the rise of the internal pressure of the compression chamber 8. It should be noted that the divided muffling passages are arranged in parallel as in the present embodiment, or they may be arranged separately.

In FIG. 4 (E), the muffling passages 21A and 21B are provided.
The case where a plurality of cavities are arranged in the middle of is shown. As described above, when the sound propagates in the tube, if there is a change in the cross section along the way, the propagation of a specific frequency can be reduced. Therefore, by arranging a plurality of cavities 30 having a cross-sectional area S4 different from the cross-sectional area S3 of the sound-deadening passages in series in the middle of the sound-deadening passages 21A and 21B, a small cross-sectional area of the passage and a long pipe length can be secured. In addition to the effects of the above-described respective embodiments, the sound attenuation effect due to the change S4 / S3 of the cross-sectional area can be obtained together. In this case, in order to secure a large cross-sectional area S4 of the cavity 30, both the rear housing side plate 3 and the oil separator 11 are used to make the cavity 30 large.
May be formed.

In FIG. 4F, a plurality of cavities 30 having a cross-sectional area S4 different from the passage cross-sectional area S3 of the muffling passage are provided in the middle of the plurality of muffling passages 21a and 21b shown in FIG. 4D. The case where they are arranged in series is shown. In this case, in addition to the effect of dividing the sound deadening passage to reduce the cross-sectional area of each sound deadening passage, it is possible to obtain the sound damping effect due to the change S4 / S3 in the cross section. The passage 30 may be continuously changed in the pipe length direction to form the cavity 30 (not shown). Although aluminum is used as the material for the rear housing side plate 3 and the oil separator 11 used in the present embodiment, the sound damping effect may be devised by changing to another material. Furthermore, the number of the compression chamber, the first discharge port, and the second discharge port is not limited to one or two, and the same applies in the case of more than that.

[0022]

As described above, the present invention (claim 1)
According to this, since the muffling passage having a small passage cross-sectional area and a long passage distance is disposed in the rear housing side plate or the like, noise generated due to pulsation can be attenuated in the muffling passage.

Further, according to the present invention (claim 2), since the cross-sectional area of the discharge port of the oil separator is made small,
The area ratio between the cross-sectional area of the discharge port of the oil separator and the cross-sectional area of the discharge chamber is increased as compared with the conventional case. Therefore, noise generated due to pulsation can be attenuated by using the discharge chamber as a cavity.

Further, according to the present invention (Claim 3), since the sound deadening passage is divided into a plurality of passages and the total passage cross-sectional area is made smaller, the passage cross-sectional area can be further reduced as compared with the first embodiment. A small muffling passage can be formed, and noise can be more effectively attenuated in the muffling passage.

Further, according to the present invention (Claim 4), since at least one cavity is arranged in the silencing passage, noise can be attenuated due to a change in cross section. .

Further, according to the present invention (Claim 5), since the sound deadening passage is arranged in the rear housing side plate and the like, and the cross-sectional area of the discharge port of the oil separator is made small,
It is possible to enjoy both the sound attenuation effect due to the muffling passage and the attenuation effect due to the use of the discharge chamber cavity. In addition, since there are no additional parts, the gas compressor can be made lightweight and compact.

The structure can be constructed without major design changes, the appearance is not changed at all, and the reliability of the gas compressor can be maintained as before.

[0028]

[Brief description of the drawings]

FIG. 1 is a simplified configuration diagram of a gas compressor showing a first embodiment of the present invention.

FIG. 2 is a simplified configuration diagram of a gas compressor showing a second embodiment of the present invention.

FIG. 3 is a simplified configuration diagram of a gas compressor showing a third embodiment of the present invention.

FIG. 4 is a simplified configuration diagram of a gas compressor showing a fourth embodiment of the present invention (various aspects of muffler passages).

FIG. 5 is a vertical sectional view of a conventional gas compressor.

FIG. 6 is a sectional view taken along line AA of FIG. 5;

[Explanation of symbols]

 1 Housing 2 Front Side Housing Side Plate 3 Rear Side Housing Side Plate 6 Rotor 8 Compression Chamber 9 Rear Housing 11 Oil Separator 12 Discharge Port 14 Discharge Chamber 18 First Discharge Port 20 Second Discharge Port 21 Silence Passage 30 Void

Claims (5)

[Claims] 1. A cylinder in which both end faces of the housing are closed by a front housing side plate and a rear housing side plate having one or a plurality of first discharge ports for passing a refrigerant gas, and a shaft in the cylinder. A rotor that is supported and rotates, one or more compression chambers defined by the outer peripheral surface of the rotor and the inner peripheral surface of the cylinder, and fixed to the outer end surface of the rear housing side plate. An oil separator having one or a plurality of second discharge ports for discharging a pressurized refrigerant gas and separating an oil component in the refrigerant gas, and fixed to the rear housing side plate and a peripheral end surface of the rear housing side plate. In a gas compressor provided with a discharge chamber defined by a rear housing, the rear end is provided on the outer end surface of the rear housing side plate or the inner end surface of the oil separator. The passage cross-sectional area is small from the one or more first discharge ports of the side housing side plate to the one or more second discharge ports of the oil separator so that the internal pressure of the one or more compression chambers does not rise extremely. A gas compressor characterized in that a muffler passage having a long passage distance is provided. 2. A cylinder in which both end faces of the housing are closed by a front housing side plate and a rear housing side plate having one or a plurality of first discharge ports for passing a refrigerant gas, and a shaft in the cylinder. A rotor that is supported and rotates, one or more compression chambers defined by the outer peripheral surface of the rotor and the inner peripheral surface of the cylinder, and fixed to the outer end surface of the rear housing side plate. An oil separator having one or a plurality of second discharge ports for discharging a pressurized refrigerant gas and separating an oil component in the refrigerant gas, and fixed to the rear housing side plate and a peripheral end surface of the rear housing side plate. In the gas compressor having a discharge chamber defined by the rear housing, the cross-sectional area of one or more second discharge ports of the oil separator is one or more. A gas compressor characterized in that the internal pressure of the compression chamber is made small enough not to rise extremely. 3. The sound deadening passage is divided into a plurality of passages,
2. The gas compressor according to claim 1, wherein the total passage cross-sectional area of the muffling passages is reduced to the extent that the internal pressure of the one or more compression chambers is not extremely increased. 4. The gas compressor according to claim 1, wherein at least one cavity having a cross-sectional area larger than the passage cross-sectional area of the muffler passage is arranged in the middle of the muffler passage. . 5. The cross-sectional area of one or a plurality of second discharge ports of the oil separator is set to be small enough not to increase the internal pressure of the one or a plurality of compression chambers extremely. The gas compressor according to 3 or 4.